The present invention pertains to an embroidering machine with a mounting device for individual embroidery hoops, which are to be detachably connected to the mounting device. The hoops consist of a inner hoop with an outer hoop surrounding the inner hoop with the fabric to be embroidered located between the two hoops. The present invention pertains to a device such as the device formed according to the examined and accepted application of Japanese Utility Patent No. Sho-62-3424.
A mounting device for individual embroidery hoops, which is to be fastened to the controlled hoop guide of an embroidering machine and consists of a rectangular hoop that can be connected to the hoop guide for the three-point tensioning of the individual embroidery hoops, is known from the examined and accepted application of the Japanese utility patent No. SHO 62-3424. According to this disclosure the front, transverse leg of the rectangular hoop is provided with a projection with a plastic foam pad as one point of the three-point tensioning. A pair of levers acting as a holder for a clamping part covered with plastic foam on the tensioned surface is arranged at each lateral leg of the rectangular hoop. The clamping parts form the other points of the three-point tensioning device. One lever each of the two pairs of levers is inserted with a pivot pin at the end opposite the clamping part into a hole in the side leg. The other lever of each pair of levers is hinged on the first lever between the pin and the clamping part. A setscrew screwed into a nut inside the side leg is passed through a hole in the other end of the first lever and through an elongated slot in the side leg of the rectangular hoop.
The device is intended for mounting individual embroidery hoops of various sizes. An individual embroidery hoop is mounted so that the individual hoop is placed against the plastic foam pad of the projection on the front, transverse leg of the rectangular hoop, the setscrew is loosened, and the two pairs of levers are moved while longitudinally displacing the setscrews in the elongated slots of the lateral legs with a defined pressure exerted on the circumference of the individual embroidery hoop, so that the individual embroidery hoop will be fixed at three points. The mounted position of the individual embroidery hoop is secured by tightening the setscrews.
The loosening, tightening, and displacement of the setscrews and the swiveling of the pairs of levers caused by the displacement each time the embroidery hoop is changed requires particular attention and is relatively complicated and time-consuming, because if the longitudinal displacement of the setscrews and consequently the swiveling of the pairs of levers are not completely uniform in this arrangement. The individual embroidery hoop will assume a different position relative to the central axis between two pairs of levers each time, so that the position of the initial stitch and consequently also the position of the embroidery pattern on the product being embroidered will also change each time, which is not acceptable for most applications. That is, the displacement each time the embroidery hoop is changed either impairs the quality of the products or requires correction of the mounting of the material to be embroidered or of the embroidery hoop, which is associated with loss of time. Moreover, because the holding force with which each embroidery hoop is mounted depends on how strongly the clamping parts are pressed by hand against the embroidery hoop by swiveling the pairs of levers with the clamping pieces during the displacement of the setscrews and it may therefore show great variations from one embroidery hoop to the next, the reliability and the accuracy of the mounting strongly depend on how carefully the operator performs his work.